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G. Requena, B. Bauer, H.P. Degischer, M. Lieblich:
"The effect of ball milling and wet blending on the creep behaviour of a particle reinforced 2124 Al-alloy";
International Journal of Materials Research, 102 (2011), 8; 982 - 992.

The creep behaviour of an AW2124 Al-alloy unreinforced and reinforced with 25 vol.% of SiC particles of different sizes is investigated. The materials were produced by powder metallurgy using two different powder blending techniques: ball milling and wet blending. The SiC particles are fractured during ball milling causing the formation of ~ 23 vol.% of sub-µm SiC particles. On the other hand, the SiC particles in the wet blended composites are in the µm-range and are aligned in the direction of extrusion. The creep mechanisms of the unreinforced matrices and the ball milled composites are distinguished by a low-stress and a high-stress region. In the low-stress region the creep deformation is governed by viscous drag of dislocations, while climb of dislocations dominates in the high-stress region. The high creep resistance exhibited by the ball milled composites is mainly due to the presence of oxide dispersoids introduced during the blending of the powders. On the other hand, the low creep resistance of the wet blended composites show that ceramic particles larger than ~ 5 µm accelerate the creep rate.

http://dx.doi.org/10.3139/146.110553